AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

DNA MAKES RNA MAKES PROTEIN

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of the following accurately describes a pyrimidine?
A
It has two rings like cytosine
B
It has two rings like adenine
C
It has one ring like thymine
D
It has one ring like guanine
Explanation: 

Detailed explanation-1: -The pyrimidines (cytosine, uracil, and thymine) only have one single ring, which has just six members and two nitrogen atoms.

Detailed explanation-2: -One of two chemical compounds that cells use to make the building blocks of DNA and RNA. Examples of pyrimidines are cytosine, thymine, and uracil. Cytosine and thymine are used to make DNA and cytosine and uracil are used to make RNA.

Detailed explanation-3: -The pyrimidine ring is an aromatic heterocycle of two nitrogen and four carbon atoms. The numbering of atoms is done in a clockwise direction. Nitrogen atoms are present at positions 1 and 3. The sources of carbon 2 and nitrogen 3 are carbamoyl phosphate, while the rest of the ring is derived from aspartate.

Detailed explanation-4: -Pyrimidine: A nitrogenous base similar to benzene (a six-membered ring) and includes cytosine, thymine, and uracil as bases used for DNA or RNA.

There is 1 question to complete.